your ingame latency is deduced via time it takes for your client to send a command through to the wow server. your display latency ( i.e. what you see your slaves do) is double that. so whatever your latency is you will see the slaves do their action that amount in ms after your main does it. about 5pcs vs 1 pc the lag will be the same if all pcs are exactly the same, and they all connect via the same router. the only time 5pcs would be quicker is when running with a low transfer router or when you are sending very high volume packets to wow, which happens very rarely. so the question you have to ask next is do you have the room for 5 pcs and want to swivvle around all the time or use the 1 pc and use PiP.